SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5bef33afea3f51029f1b0333686fbe4f40b3922d9ba33673ef286778d11363ed' 
  AND token = 'r+ATlCNwpGYKg8zvDwF+8N3/AYHlnJVA9mdOxaOPx1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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