SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c102f189ba5a53a55db42396d7aaab65bf45179119a8a8b8cba31be685109c7' 
  AND token = 'gAXbkWLDXnGXxewnz2euLdw4Jmb+fZeHV71W2SDmesw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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