SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4775311bf4ab16a0ffc90447a2d2b4aa91db4cea68ae1376a238fd9b120c236' 
  AND token = 'YyOp8wH+jG7HDPpXuvZcIYb+Je5Vu+kMTFFtbosT85w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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