SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52432eba38880f26eaca5204b733bca18af4e4ff9fd1542d3ab1713b293c816c' 
  AND token = 'VQ5uqolYA0506TsjsgtM/F1NLcgGxVixe0iUGMOuKfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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