SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1d7f01cdf5b6ce4ab6df12cdcf5b9196f1d5e0d2da8cd6ebe30cc8a8b48f989' 
  AND token = 'r411OqjwUUFHogtA/tmh2sMh6BKCTzoZa27AQqk6GvQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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