SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b7220bcab7f245533dca744b173f6872a9fbfa5634a21d0ddeb14a1aac87b24' 
  AND token = 'r+O7QGJjmaH9byw/l2WBWO6qRKw2w7fzuG8tfEDprYA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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