SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '639605ebf61016515c460df7f16b2f75c543c55addf311f36f8fe063f8e62e63' 
  AND token = 'H/VKNUy7yC8XV+pRoov2Bh4JsSyrqTymc7B4CcBVYGU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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