SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '0be55b72a50c03f61e804c9f6c639799858f918528cdc0b58a1ef113bd3093d5' 
  AND token = 'wkmjaSsdogepyBs5Vi+t2WTwaiB+2KsfUAwEcgw+RuI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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