SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f25cf44bf7b44858d1ebb598650463cc5b0db68ae6dd4c455e5694c37d64143b' 
  AND token = 'MhT+eD/LYojRhony4LJGpgwmSHHwuXUrGifMphyHEvk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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