SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0a3c14b14c982c183782dc39773bcd24550d17f7c7c2794a184a9d8216b313c' 
  AND token = 'K8inKp5fRmqGyYiWjwJz0SKs9HhY8+sJvnjOlA8hEuk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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