SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92bfedca85d0ee02dd2574af1cab7e6a13ac11a8b06b18247e68964da6a9a0b2' 
  AND token = 'FGiJFBvKQGgbvHpyEGef13X1FB0ykDpIUGXlY6cp2Wk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}