SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c2054309ed276c968819add6a7ecd3889c86b8042cea48047c423360ee16dcc8' 
  AND token = '+nVm/BY6zrVLhKf0vNnepLmGqcbRfaf/ckXbw5FjLBM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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