SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ecaf0d65bd1cddb30b7510c83d10ec1e170722b344ff92cddef24336f18b3d6' 
  AND token = 'YKgxnIEQWjDtQ9lb0vCLyrDzqN3oxcbhxL62eM6Hpjc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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