SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4ce2d27064df8711eb4adb3ea05d139f96e2152946fc4d3676e7d76b473d0047' 
  AND token = 'O0J7pqVtz8YmKKd9ul3wNvMIqYhTIsm9QZ20mTOr6GA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}