SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd035d91dad47b4d876ed31706582df8fabadcd2b0fb96b12aa856dfe205b8f15' 
  AND token = 'LsE2K0RZ9H5Zj0E4/V+knXCYu+NUDqsys2JwWXGEMcU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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