SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a59d11a7ebb61e35e3f1c3b88911b05e4fb32d2e1a3cd0f772e68583205ffbb' 
  AND token = 'ocnpVsAZVtivZ2r2ttAag2dbXZtftlJfpZuYFb8pLvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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