SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33bab4a760a9892fd43e8e59f5704c1f92d3e2983737c6dffd294763d0a4f146' 
  AND token = 'vKcnXKtKBFfcjrgu6ygopX4zwNPE0mXcxKJoG9xju1Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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