SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6996a784ff03716304990111d6b6008117597fdb266fb73b90f5912061d6f1e1' 
  AND token = 'BwMUqhKDQtZ4HiRdhQ8QQVvLInic5Yncj8vFt7g2FpM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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