SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdfcea7997b0115448c11d14b1f1335ac0aa56ef7edd05e18f7a4c8a93214b89' 
  AND token = '9wQxFayUjYG5GaBAPhL+dTfV9sKJni+OEebopLnt8MM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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