SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6523d80d59ca7535de1d7cd0244e9bccdba5396a5244d8b901b1d48fe2e2d851' 
  AND token = 'jx9g4OwiPxOqxTIak2c19FeFIKH1kQ/rURnZdfSPxCQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}