SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '865ad03958bd354f61947e31015b4c3ed2479eb85eca1bfe31465f30aadd4b73' 
  AND token = 'M7aDMfGqUakyBTxchffhPuZnmgRbrZ8OYuv7f++nYME=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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