SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa296f99d7157a9d977feb72d34fa73f08d800238d4254dfb1ba1142a461735a' 
  AND token = 'X3fbFhVVvrdsgVL/amZCB47popZNJfSJonxwPfEgLd4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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