SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebca0ebffc1060bef43ddc5f85eddefffdc4f9546cfa93d9434090c971f91a14' 
  AND token = '9BCJLm4KZvroaRsPYpdwYqzGSr08JFEqY+pLlnn8GcM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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