SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2330c56c80fcdf5382c57203799b515ceb96f492d78bf5dc453138e0afee1ad6' 
  AND token = 'C1jxHPYs32eh2hUIPinE2C0GiPWxFFdtEfNwYnhdtIA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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