SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7bbf4884c9544a027de8776907c8661b031083b7f322465f8413f0388fc4591d' 
  AND token = '0JylbyeroqYuTNNs/Pce0ONCyiI6RjFgLMRL3pV3F2s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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