SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1ceaea3d71a4527b3122e6ddb18e0a143ae8c4d07e7bd179bc6d8ce711ebeb88' 
  AND token = '0yvtAzwb3WfqIXPu39fXAg3lhz6tDVIdq7HBdZwVinI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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