SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d22ca5ec61a88774a5ebd34e2a3251c722f875f87eac6b418e753f04ded8255' 
  AND token = 'vk2rU4/5td9yTWgRRqp/OAI8W9IF77M58NBgGuCflt4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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