SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ce7d7fb2baa9884ff40252bba6d05ce998c19c8f2332b835ae37646c17dac94' 
  AND token = 'AheJXSNZ2ZyWNvpv8+g9Oa6rTLSvyaMgTySFLE9RLjw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}