SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1c4846ff8f411194de936f8afcf9342f1d4e56b8306cbbdc104b7217b00a2da' 
  AND token = 'dEJtqbpEJughxe99KggribDN+q9IFkj0n19mcldBaaA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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