SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '422f525e7089faaf5cab54b6d06314b20319787cdae32d14713449b1551009d2' 
  AND token = 'OmjrejhbeFi50KnRSrbgPuFmDlgk0UI+4kCLGHk7Iyk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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