SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e5e12828abaa5384e154f84dc5d4dbd7f3acca5232df26c3cb832142ef4204f' 
  AND token = 'AgiOq+t5ZBqoV6xfEZIjDholict9KsKznZM6zsY6J/8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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