SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'acd12c7f387b97dde7ad2622d26bbb1589da86590205830dca7adbb1c0dc6271' 
  AND token = 'DdQiyPFfqX/VXRaBfZkxcfxgZEvGXrk52b5jQ1qdzHA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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