SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb97aa19ac29644c47810a8aef3e35391023937c21e0abc1fd8aea5724244de3' 
  AND token = 'BmFJkc7TZJY17n/5kLZq+f9hdiSMF6Us9OjWZgukc3c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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