SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '779c8a782041c9e3e08950241651e89765179ec83907fa83e3b1b7de9ab6dd54' 
  AND token = 'eFszKhJUAy2fwZe15Nn8q6RVtPeX4PLYQXOGfztDhrM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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