SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd870170d16ab1d0f792ebcdfd6999912bef28ecb4e04e4152643622cada38d78' 
  AND token = 'TAObaompgfbUmd/aB6rYqUgHLHwuxeGNYvjVgAtLsdc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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