SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a4c3c988459c2451438463f6909e6d419cf8eecd78b05c81f47960a9642519f' 
  AND token = 'RM+JfL4nvlfjGbZ4zKFIlL0JwrVKvVyeVO2ep4l3BBY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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