SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9413f8a6565a71269374ac7de24adc56766c4c0118f32b56816c9980844e929' 
  AND token = 'kFwLLOOpyqJpcmmLJK3pINCMJGT/SvNqKTIPXPX71bk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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