SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'c9bbbe5291741c1e397ddfdf326a6d4ae712fafe90e80c87c32af9d6093be069' 
  AND token = 'KvR+zH8p0j3pz/jK9QrV/ApJL7dQeAIYDfnqmP66/nw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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