SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7369cc3811eca7be36c5c90728aed13f3d65230359d953120fa1c8c2cf68e894' 
  AND token = 'd5xCBlhJeJJw3hvHYVRt+z5IVlKbpjKUcC6OJ1HGXwE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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