SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b7b1e5772f8bcf31ba26c575347fda909ab214d4e7e00735afbb13e1fda1ad8a' 
  AND token = 'O+IccrTFwJAtmuA0Pw+swHoj2yzu+BhVAg8OnrQmZUs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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