SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0cd36062acc893b87c3055c651b565d0ec764b8230aa7af0a806dbf25f80032e' 
  AND token = 'zHAvnoQD//A389lbHFJXQ2cNp61UzZJYYFBOZf4zU0c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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