SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '0ef8b59a05f2751eaf1948134d1523e3f385d4fc00aa66aaf48cf6bc97a5e650' 
  AND token = 'yF1Nk9+CQHSGeuXD8qBezAqr0NntexFspuGCrSRoeTI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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