Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a5a4f214a37aebcc030a2b2b96a4e349dc62a11f603a2b16c9a49e9c663ab0e' 
  AND token = 'Gndf5NoF67dDv9eaOPdkiJGduzLN7Ll0E4/uaSqjWdQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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