SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08ec70140d080422475101e6150f772349d13135f1225f6282dd7b3d170e9cf8' 
  AND token = 'ddWhRBKWRX0i1PJUY+eOOzwHUMojfAtgURhpTGj03fs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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