SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'df604cd8d6fdb8fef22b3bed67763ac055420f28e5991c239761dd14c7298a5f' 
  AND token = 'dRbngMvOJirJD6Ho5vMcHq4XweUOI/yNak1BztKMSLk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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