SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '079b71ddcfb7a6411adee8dc5ad64c484d6235db49f9fe5f05550620cc0cdf52' 
  AND token = 'J+QTWkEe0T7JrXRNgpTKC/HBWYrKpPSHH0rRXzIaqR0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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