SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8dabaf18ea82b2e8cbcad379a0b9f648ec21f79c349b5b4087357a3382f4cd10' 
  AND token = '/3IiFISEJ6QorScYPrLyLsoMr9GCWlrMtxn3W83x7BQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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