SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef18a16ec39c1e03130e3da0a587a797509daaae2cf1159c69110f219ff221de' 
  AND token = 'pkqWVMtg/XT+dqZwgDo9GXjR2qs3ILoFN97Y5Q8wENE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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