SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4605d5d5cb57abf0945832f629a3cb11f4998481fc24b9bbd254f5313c6563ad' 
  AND token = 'ya7Y7L2MBNzJdLfBs4cZrPFfaVB3tZDxaWRBsowx1+Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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