SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8badccce9701b35e54f81e4cee353c327bb36ae36ce07f9d7c04a6e9aac5e641' 
  AND token = '93whCO6EK/8R28GJZj+F7jJwuV7YB+njyBd5MsP9eQg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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