SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78c230b3d3110c2b0001682a2f5ac7b288a989da8ba4a4d24af7976a6cbe3dfd' 
  AND token = 'hWWjRkPoWJOat/imCUPYAFwWvq6DbPhSPm70HKX7phM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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