Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a545d1b10712e54fbc55c26dc77cbe4d9004ade6c56724241034d7742689f6a' 
  AND token = 'q4yhJtB5PEDrcxDmiuAQ0WFgDN93yPTmU8+m0uJXhe8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}