SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb13cbba976ce91284a074a5309d5173cc1bd8770ee7889a1afb76fcc711c19d' 
  AND token = 'WTzrzNvvtf89PuynChfM0x0NjEGqcgceemih5kNyuJ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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