SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3e308b88b5da1bf83ac4cc4fc6e80b16f6059e1265fd6c72320d146a266a5d7' 
  AND token = 'JLV8r76cDwrZn/KKAxN8axTitZr/flTz7z3xrKIIM6A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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