SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '790aca427b00f0309a4ba9f9a786cc86dc8749577c1a1d718c18a9698972e6c1' 
  AND token = 'v98p1hqflnso6GZkhDyl1dY6iuhqvArW6mPj/zwG1Vc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00062

JSON explain

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