SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b55c81ca6ac08831fc692d6a614dbb1b1ce59db5e42015f2e979f634642c47c7' 
  AND token = 'fZ1nfSNC7+OCfvsWuwiJr1OkX160JCYxTzjcXIUPxSI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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