SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fba3ed59bffc2b1479b12c2dab66accf75831af0350e99c224a004613edebe3d' 
  AND token = 'jSRr1s7O+4Y6OW7g/jXeqx/JFlOLxQypHohe3PnXFqM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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