SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '908f4c248144c10163f303f6648375d4ff89cd6e29f6a8e1ac89c18703f0365b' 
  AND token = 'waKV/3l2XRcElHlXRIexyTgpadInbDPMFxjj/HBK8J0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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