SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dba310fd71f340b5f3c77dfc189234f924aaaf7bb8200627e654bbaf418c7796' 
  AND token = 'cYmzPwUyxc/ksKLArIHI9TJPED34mRfiK8qPK+5VXtY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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