SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19cf330d032ef25c57777d4b4ce134ca73a9732521b68e645f1a6a3464682b9d' 
  AND token = 'UmjiSwpTVjiglwLE98LY3FWCgf3vUDONuraGIbOrLtU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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