SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7da8aef63f5664571e23c699d070d6753fcf4681dc26f4a15c9057d4943f1cb5' 
  AND token = 'tHlLlG792iAr4wWXDjjB1T39t72VszTYiPJGWcSZvDU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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