SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ce100ff09b99ef522890a49f460500bca260eaee75b9094915820e950b82bef' 
  AND token = 'UWM7ZGKTTLPuTm3+QSRWcN/tHn66Xol9Jso5k65dOhc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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