SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7d18f8451a8af81fc9a1c710892edba566127842282a0114192ebdb500cbbd60' 
  AND token = 'ZUINKILkeb3BnCASfzf2p6/KUGOOeGFljDgEuqwVUzU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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