SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '948aae5939749c3d6ae9159e0bf554ad9c5d28f4f0b5863213822ca4a86e63fd' 
  AND token = 'MHEYLEFL+vxYnIZb7w8BpPqnJ6+W6EzP2ZhEPB2B0V4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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