SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5abcba789a710d3d3eda573031eac67ca716c3749109ad4230e32b4cdc4e81c4' 
  AND token = 'YINtXwD0zEz7KTKJIQKgOwTjKDpn6v3f8s94lBPXzYk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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