SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7effda6bd12edc8af39fac2b1284daeaa966fa25e4ce512a97de542386e67b3' 
  AND token = 'JzP0mVE6DqfuXpOS3oPjd7t11x10/IdYQ1H0auMxrZs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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