SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '6c8e4995404f1a0b978dd81ffebe76e6184530a59b95d1b20d5d1742a5c748d8' 
  AND token = 'drnY0Z4Gulfe+suvLD2TexfdMkVEaiLEo2bnBmcKxRo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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