SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5224035d3ef280b252afb0aadd55140fb3ba6540db121d78c8415e11d6932f95' 
  AND token = 'XZ4Dp7mwn+Pd9ZcLx9WJgJ1r2f6kO8VDV/yvTbkSUpE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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