SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b3f79a34a0ada1bbb8cf799393647ed1ba9b44d1376fb1b2ecea73ee580b0fa' 
  AND token = 'IJHBoywLmGndpEb+IznJ+DmHQnqjwlsgRFKNzV5gduw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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