SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd524174f9696e2cd0ed7e1def2abc828791ca48ffe06da242448136f83f8d1f' 
  AND token = 'uZctUoLamwU9NiSPkbffI0U1HNHF1NRHGbqg0oJp6Co=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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