SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7e4af482d2a6142cb4ed98281972f62b1d1aa19487cb069df35ae25d4771b896' 
  AND token = '9y+CCxTy5JV60NKO28M8BvBylzclcG0myZqflLXJv8A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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