SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3f9f310743d5ca4d82ddbbf6e54c07bd5bdceafaf48aa9fe182f6d695a070af5' 
  AND token = 'Wghh2/AOKgslwvAtr56f/sT2t1/aH6XwAokeMTwUTjM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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