SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '304d754a339471f7630a502b99640a41bebbeb0a82deeecc821b8ac2dd1ebf87' 
  AND token = '7TzIWgjll9FnQ+MCDs2PL9PwKQYqoWGJxYFoCOPYRPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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