SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ceb813c07166eedce4238428a2787110a1c432c23c5a9866f152b76001ce7a33' 
  AND token = 'Y1kiUqhTsbxLoy9PKIUsV3kgm0m76SStpg8p/nN4mqI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00083

JSON explain

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