SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c7782e5aeca182595767d80214bb5c62f2e04e765efce80688c08fc567bd04c5' 
  AND token = 'yNjUYYPfgHFzNdCHnqL7XhovF7dXLOFN7nGZp/m7uu4=' 
  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"
    }
  }
}