SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf23276687839b16017517ad1b09536e46c686f6cc399e68bcd2a44a600f9e94' 
  AND token = 'oWUKUxs+wTkT1XWnLE+/DSC8vVrMJkCtUdgPmzpJq8s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}