SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '699508730eacb1e4748d5fc1da841dd8d1829714f93959cc66c5ec628ee82f56' 
  AND token = 'tKhy2mLZ/mneIeUCj2bNQwyGcSq6mOxsTULD2Dj2JTs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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