SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5054536c6619abef7b9ffeeaca192948c2bbf15b89d5bdd67f9912abd8ab971' 
  AND token = 'onx21AnOc+r754WbT7//YbW938Yc/0KWtXshAufv0ww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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