SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c72bffe3b9b4482899bf07393154f301fe87cb19ea51e7ddd5537f516e9d603e' 
  AND token = 'jlJVYU0wOVrXUNC0yD/b5OH/Y80AuRJSqhMHSP6QySU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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