SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c90278aa28e59918241545cddee800dc94ac9810296b5efe1a336259cd5e0cfc' 
  AND token = 'Z3ebWfBj6emociiqWodGbzOebfgVXfPrxpAa4+Dx0go=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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