SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec4583d7da45eae1f3b8295f284195ec1fa5c9834eaa2406c2f92ad759903219' 
  AND token = 'y063z+nmzm7pfRp3qB8R/Y65XFYiOmxmZApgGhsyKdY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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