SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '087f41018cf1983458a664acf62f0e554c39db40d4023ca74b7ebc6e27509820' 
  AND token = 'c1y6tdA+Ttk4l8OHFjtO74dX58EwXnOTyKTVouvKgrM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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