SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '941c2f9a8b069d4c99aefe9f1c197feb37b59d70b612b9c857af19f1c44d22e8' 
  AND token = '9KatsimIjsGxBBVvcKehcnFv/ED5qj1dRurjByYZOJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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