SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd65b315e13f02edcca5e71ef05437edc130543310afdf06bd040657bbc363cb8' 
  AND token = 'L2QEAbU7WPANboWTSQLhmYTxdKrZaql8962X5cNeaSM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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