SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '618705cbd72276d31558c2b0d7c39152b64e96846f07a543f57d964fa664cd06' 
  AND token = 'V0F0KsQK68Pk6QRbMW/RhQbrtqf6zBGmmhrxfzRgIvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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