SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7eddf179efe5da40cdb86eb536317cbe7d2743072d8146fe8d6718ce1907b083' 
  AND token = 'HhcNzS0UEpjLqmyveM9hgzK7N/hFQ/vp9gHDoRKSnWU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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