SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '714260fc095d1df814b5188becb37ba588905cbb3105ce70903e8bfd8cf6853a' 
  AND token = '8s+grRXT7DtqvFdSolAbIWqWcr12gTLkTXJDAsHQA+Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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