SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '0c3a18e7047ca809664974ac8b908d0db73d3dd0744e8110a18304df35a485a2' 
  AND token = 'Y/DJVdoUWDzLm7W7Gm66M/N2gTuYH0BzYdcvs7JNwLw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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