SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3952444ed09e74235c16b984b55b15d7cc5b7714c91bb130dea13abf24012c78' 
  AND token = 'qzHIwRPKjRfqsqK5WMYHe6isx4KM42jzZrBPzoUNDUw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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