SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef753d1044a7f67dfb05cd91ac3c4fde257806468e1049991feb624a8d4c899f' 
  AND token = 'eoFRKfomGnHf2YPwJFIAqszHZ7ctY+2pCBZfyI/WH4Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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