SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfacc4a08aed9a1eac4b580ad847dc073c2659dedb9d783362279bfe24bb7302' 
  AND token = '15IwySEJwJWKN3lzTGf3C+VWQJ9KHCUuDy/hiKXwJ6I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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