SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'af784941f9477257c1dbe135fb068e00974fe57f5338481ec56fbb94d9282ac5' 
  AND token = 'KonCkdRF1O6doA0jzKVXq2piaSfvHauakQ4X+u7KJWM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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