SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f323775cc0f4b278f5e84804432a4e5c4ae80ba87ca505370e6d8ca84f1c2ebd' 
  AND token = 'T/NveYfkVgNXd+29GKXPPKrVwliLmndY3SFmSSzNE0w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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