SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cda8299fa252cfc9724dbab2d94df336f9cf6e156f7536a102e43eb410820bb0' 
  AND token = 'jua9Xw4Q/wrpinVr7FbrBh2mKb+RGwYny/4lOUqYCMo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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