SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d0fb8cf3c675e6bc961ae4175103965abfe37dbfc0a76ee41eb52eca69052c0' 
  AND token = 'ZhFV/XLTk+PF2V9UWIHROXp/FPFkeRppohW6k1b3Ht0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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