SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9361d284fc992758ce8b7ab13a3e04976f77023b69448185baf232256e7abcb8' 
  AND token = 'DMCFVB+OXHx+fVudn7TzELa905lg5iaZSK/VMwNgFPo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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