SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1e7d3f2d829941707124de39a2b184bd8b4211607dd9b84a528ec3dd7b889b0' 
  AND token = '/oJ/TyzMJMPbQiaYhHVp5Ql0F2ZIBSJkHMCj+O+YQFw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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