SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92071c2565ae9cbea6147b73380cdefca2421cd38e5c03c3cdbb8a2fec10cc92' 
  AND token = 'BwBnSo5yRsXl/w41Ysv4L2+v/3TEIWGbJPtGluqyQQQ=' 
  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"
    }
  }
}