SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f82539d4be98ac42ff88fada20c9524c911801904178f7338fcfc719c0ebd531' 
  AND token = 'gBqHnnYTmwNCtMr2O0n3QVZmxHxHohfNURqDXrdTDaE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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