SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d78a6790257aa15c9c68a80366b8607a06bec41a6333b3f28abaca66be1fafd' 
  AND token = 'ADQHg2YvzeBjOX4H24tmv57seQP/SYpYt9Om8hcBu8o=' 
  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"
    }
  }
}