SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9a464cc6e8362b1df06403d0357c6f34758264b31a02a676db12067fde08b31a' 
  AND token = 'HETDTaEmoCArZE6BqLyTb+GdT3LCTajqpySZEASzH+Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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