SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8256417a7576a3c05af431ef25063341570a69d92911190370bf7cb446d7c01' 
  AND token = 's+fJFuWVJ7DjGqEp7fVOU18Tv+WilwfGqvShIqOBOo4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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