SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78841b8d024c34b85adc308b6305eeaa6115efca025bfe05693b6bb4238e937d' 
  AND token = '9oFULdjX1BFd2g2I651q/Ha4tR9StNh0q3Z+yvR+Xss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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