SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '901ae9c13da71fb591b95730cf1bbd693bd5813eec62c7c50b8076b290148c3a' 
  AND token = '2fG/RMtWJYqzROLQrxMXLOkpstcfcu9fsqVU1zU4Zgg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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