SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80116043ae51b8dfb9e1ea466ee23f5d28fdde45cf2f9dd8e9e95799c5e3d57b' 
  AND token = 'WIySQSh9K8HgWrh1Yvidvtxv7C3unEVGPUWjWzDpcNw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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