SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43bbd9ca891b995e13c5fed7276182b6a5cdce31951ae986577bf5ea7fcf3bdf' 
  AND token = 'lRzEtmfyoyyg6atDuINY3RxHCmhTiiVLbGWffWIHpuY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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