SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '87047704985c2e968b15b7c76760f48693288bb1f442b6369a583a9a6ceab1fe' 
  AND token = 'n32ll72GLMXqv3pBf1oSry+d99ALm25ZaxKRcot60vw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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